code: def test_arg():
      x = Symbol("x", complex=True)
      assert refine(arg(x), Q.positive(x)) == 0
      assert refine(arg(x), Q.negative(x)) == pi
  
imports: from sympy.assumptions.ask import Q
  from sympy.assumptions.refine import refine
  from sympy.core.expr import Expr
  from sympy.core.numbers import I, Rational, nan, pi
  from sympy.core.singleton import S
  from sympy.core.symbol import Symbol
  from sympy.functions.elementary.complexes import Abs, arg, im, re, sign
  from sympy.functions.elementary.exponential import exp
  from sympy.functions.elementary.miscellaneous import sqrt
  from sympy.functions.elementary.trigonometric import atan, atan2
  from sympy.abc import w, x, y, z
  from sympy.core.relational import Eq, Ne
  from sympy.functions.elementary.piecewise import Piecewise
  from sympy.matrices.expressions.matexpr import MatrixSymbol
label_desc: Use image node_id 11 for calling a global function with example usage: test_arg() without return types